Pitman and wrist pin



Aug 11, 1925. Y 1,548,914

G. P. SLATER PITIAN AND WRIST PIN Filed Aug. '7, 1924 3 Sheets-Sheet 1 Aug. 11, 1925.

G. P. SLATER PITMAN AND WRIST PIN Filed Aug. '7. 1 24 3 Sheets-Sheet 2.

G. P. SLATER E'ITMAN AND WRIST PIN Filed Aug. '7. 1 24 3 sneetsheet 5 w a I: f N

Patented Aug. 11, 1925.

Wire

stars PITMAN AND WRIST PIN.

Application filed August 7, 1924. Serial No. 730,743.

To all whom it may concern Be it known that I, GUY P. SLATER, a citizen of the United States of America, and resident of Tulsa, in the county of Tulsa and State of Oklahoma, have invented certain new and usefulImprovements in Pitmen and Wrist Pins, of which the following is a specification.

This invention relates to pitmen and wrist pins and has for an object the production of a pitman of special utility in connection with the drilling and pumping of wells, and it has particular reference to pitmen used in connection with rigs for oil well drilling and pumping. r v

A further object ofthis invention is to produce a pitman having unusual strength and durability associated with quick-acting bearings or boxes which coact with the wrist pins of cranks.

It is a further object of this invention to produce novel means for producing quick action of bearing box members, one with relation to the other, in order that they may be assembled in operative relation to a wrist pin or moved out of coactive relation to the wrist pinto permit the application or removal of the pitman with respect to the wrist pin as the progress of the work requires, and it is a still further object of the invention to provide novel means for retaining the movable" elements in positions of adjustment against displacement except when manually operated.

It is a further object of this invention to produce a pitman which will have unusual strength and durability and in which the parts are readily assembled.

With the foregoing and other objects in view, the invention consists in the details of construction and in the arrangement and combination of parts to be hereinafter more fully set forth and claimed.

In describing the invention in detail, reference will be had to the accompanying drawings forming part of this application, wherein like characters denote corresponding parts in the several views, and in which Figure 1 illustrates a view in side elevation of a fragment of a pitman embodying the invention;

Figure 2 illustrates a View in elevation of the edge thereof;

Figure 3 illustrates a similar view with the parts in different positions of adjustment;

Figure illustrates a sectional view on the line 44 of Figure 1;

Figure 5 illustrates a sectional view on the line 55 of Figure 1';

Figure 6 illustrates a sectional view on the line 6-6 of Figure 1;

Figure 7 illustrates a sectional .view on the line 77 of Figure 1;

Figure 8 illustrates a sectional View on the line 88 of Figure 1 on an enlarged scale;

Figure 9 illustrates a sectional view on the line 99 of Figure 1 on an enlarged scale;

Figure 10 illustrates an enlarged sectional view of the means for retaining the parts in adjusted positions; and

Figure 11 illustrates a side elevation of a wrist pin adapted for use in connection with the pitman.

In these drawings illustrating the preferred embodiment of the invention, the two sides of the pitman and the yoke are formed by a metal strip 15 suitably shaped to form the yoke 16'. The two parallel portions of the sides of the yoke are connected by a web 17 in the present embodiment of the invention consisting of an I-beam whose flanges 18 and 19 are secured to the respective sides of the pitman by fastenijngs 20, such as rivets or the like. The yoke is strengthened by a brace 21 consisting of a channel iron whose flanges 22 and 23 are secured to the sides of the yoke by fastenings 24 such as rivets or the like.

A box member 25 is secured in the end of the yoke and preferably it has flanges 26 which bear against the edges of the yoke whereby the said box member is held in place. The box member 25 has vertically arranged apertures 27 in each of which a guiding post 28 is secured, the said guiding posts extending above the box member 25 for a purpose to be presently explained. The coacting and movable box member 29 has flanges 30 which embrace the edges of the yoke and the said box member is ada ted to be adjusted into operative relation w1th the box member 25 after the pitman has been applied to a wrist pin. Preferably, the wrist pin sockets of the box member are concaved in order that they will coact with a convexed wrist pin as will presently appear, although the inventor does not wish to be limited with regard to these details.

Suitable box brasses 0r linings 31 may be provided for the box members as those skilled in the art will understand, and as these linings may be changed to suit particular requirements they will not be described in detail.

The movable box member 29 has channels or ways 82 into which the guiding posts 28 project and the inner faces of the said box members 29, in the present embodiment of the invention have seats or recesses 33 in which the ends of springs 34 are seated. The said springs 34: encircle the guide posts and they are of a nature to exert pressure on the movable box member tending to force it away from the stationary box member.

The outer faces of the movable box member in the present embodiment of the invention has a concavity 35 near its ends into which cams 36 extend, and the said cams are operative to force the movable box member toward the stationary box member to adjust them with respect to the pitman when these parts are to be assembled with relation to one another' The cams 36 are carried by a shaft 37 that extends through the sides of the yoke and the said shaft may be provided with an operating handle or crank 38 by which the shaft may be turned for operating the cams in forcing the movable box member against the action of the spring or in turn ing it in the opposite direction to permit the spring to force the movable box member outwardly.

As a means for retaining the cams in difterent positions of adjustment against action of the springs, the outer sides of each cam may be provided with a plurality of recesses or seats 39 and the sides of the yoke have recesses 40 in which springs are seated for forcing balls ll outwardly into certain of the seats or recesses as the cam is rotated.

The friction retaining means may be employed in connection with both of the cams or under certain conditions perhaps, the friction devices may be employed and associated with one of the cams, depending upon the requirements in practice.

The wrist pin in the present embodiment of the invention has a shank 42 that may be secured to a crank or the like, and an oval pitman box engaging portion 4:3 that will fit between the bearings where the box meming the bottom of the strap member, the said bearing having integral flanges extending across the edges of the strap member to aid in anchoring the said bearing, a sliding bearing section coacting with the first mentioned bearing and having integral flanges projecting into engagement with the edges of the strap member whereby the bearing is guided, a rotatable member having two eccentric portions, one near each side of the strap member, means for turning the rotatable member, and springs interposed between the bearings in line with the eccentric portions of the rotatable element whereby the eccentrics exert pressure on that part of the bea ing which is engaged by the springs, as and for the purpose described.

GUY P. SLATER. 

